<!DOCTYPE html>
<head>
    <title>
    计算属性
    </title>
<script src="vue.js"></script>
<script src="https://cdn.staticfile.org/axios/0.18.0/axios.min.js"></script>
</head>
<body>
<div id = "app">
<p> {{ currentTime1() }}</p>
<p> {{ currentTime1 }}</p>
<p> {{ currentTime2 }}</p>
</div>
<script type="text/javascript">
   var vm = new Vue({
        el : "#app",
        methods : {
            currentTime1 : function() {
                return Date.now();
            }
        },
         computed : {
            currentTime2 : function() {
                this.message;
                return Date.now();
            }
        },
    });
</script>
</body>